Sentinel Lymph Node Biopsy, Lymph Node Dissection, and Lymphedema Management Options in Melanoma.

Melanoma tumor thickness and ulceration are the strongest predictors of nodal spread. The recommendations for sentinel lymph node biopsy (SLNB) have been updated in recent American Joint Committee on Cancer and National Comprehensive Cancer Network guidelines to include tumor thickness ≥0.8 mm or any ulcerated melanoma. Mitotic rate is no longer considered an indicator for determining T category. Improvements in disease-specific survival conferred from SLNB were demonstrated through level I data in the Multicenter Selective Lymphadenectomy Trial (MSLT) I. The role for completion lymph node dissection has evolved to less surgery in lieu of recent domestic (MSLT II) and international (Dermatologic Cooperative Oncology Group Selective Lymphadenectomy Trial [DeCOG-SLT]) level I data having similar melanoma-specific survival. Treatment options for the prevention of treatment of lymphedema have progressed to include immediate lymphatic reconstruction, lymphovenous anastomosis, and vascularized lymph node transfer.

Planning for post-pandemic cancer care delivery: Recovery or opportunity for redesign?

The delivery of cancer care has never changed as rapidly and dramatically as we have seen with the coronavirus disease 2019 (COVID-19) pandemic. During the early phase of the pandemic, recommendations for the management of oncology patients issued by various professional societies and government agencies did not recognize the significant regional differences in the impact of the pandemic. California initially experienced lower than expected numbers of cases, and the health care system did not experience the same degree of the burden that had been the case in other parts of the country. In light of promising trends in COVID-19 infections and mortality in California, by late April 2020, discussions were initiated for a phased recovery of full-scale cancer services. However, by July 2020, a surge of cases was reported across the nation, including in California. In this review, the authors share the response and recovery planning experience of the University of California (UC) Cancer Consortium in an effort to provide guidance to oncology practices. The UC Cancer Consortium was established in 2017 to bring together 5 UC Comprehensive Cancer Centers: UC Davis Comprehensive Cancer Center, UC Los Angeles Jonsson Comprehensive Cancer Center, UC Irvine Chao Family Comprehensive Cancer Center, UC San Diego Moores Cancer Center, and the UC San Francisco Helen Diller Family Comprehensive Cancer Center. The interventions implemented in each of these cancer centers are highlighted, with a focus on opportunities for a redesign in care delivery models. The authors propose that their experiences gained during this pandemic will enhance pre-pandemic cancer care delivery.

Distinct chromatin environment associated with phosphorylated H3S10 histone during pollen mitosis I in orchids.

Pollen developmental pathway in plants involving synchronized transferal of cellular divisions from meiosis (microsporogenesis) to mitosis (pollen mitosis I/II) eventually offers a unique "meiosis-mitosis shift" at pollen mitosis I. Since the cell type (haploid microspore) and fate of pollen mitosis I differ from typical mitosis (in meristem cells), it is immensely important to analyze the chromosomal distribution of phosphorylated H3S10 histone during atypical pollen mitosis I to comprehend the role of histone phosphorylation in pollen development. We investigated the chromosomal phosphorylation of H3S10 histone during pollen mitosis I in orchids using immunostaining technique. The chromosomal distribution of H3S10ph during pollen mitosis I revealed differential pattern than that of typical mitosis in plants, however, eventually following the similar trends of mitosis in animals where H3S10 phosphorylation begins in the pericentromeric regions first, later extending to the whole chromosomes, and finally declining at anaphase/early cytokinesis (differentiation of vegetative and generative cells). The study suggests that the chromosomal distribution of H3S10ph during cell division is not universal and can be altered between different cell types encoded for diverse cellular processes. During pollen development, phosphorylation of histone might play a critical role in chromosome condensation events throughout pollen mitosis I in plants.

Cellular localization of mitotic RAD21 with repetitive amino acid motifs in Allium cepa.

Onion can be used in experimental observation of mitotic cell division in plant science because its chromosome is large and easy to observe. However, molecular genetic studies are difficult in onion because of its large genome size, and only limited information of onion genes has been available to date. Here we cloned and characterized an onion homologue of mitotic RAD21 gene, AcRAD21-1, to develop a molecular marker of mitosis. The N-terminal, middle, and C-terminal regions of deduced AcRAD21-1 protein sequence were conserved with Arabidopsis SYN4/AtRAD21.3 and rice OsRAD21-1, whereas three characteristic types of repetitive motifs (Repeat-1, Repeat-2/2', and Repeat-3) were observed between the conserved regions. Such inserted repetitive amino acid sequences enlarge the AcRAD21-1 protein into almost 200 kDa, which belongs to the largest class of plant proteins. Genomic organization of the AcRAD21-1 locus was also determined, and the possibility of tandem exon duplication in Repeat-2 was revealed. Subsequently, the polyclonal antiserum was raised against the N-terminal region of AcRAD21-1, and purified by affinity chromatography. Immunohistochemical analysis with the purified antibody successfully showed localization of AcRAD21-1 in onion mitosis, suggesting that it can be used as a molecular marker visualizing dynamic movement of cohesin.

Random BAC FISH of monocot plants reveals differential distribution of repetitive DNA elements in small and large chromosome species.

BAC FISH (fluorescence in situ hybridization using bacterial artificial chromosome probes) is a useful cytogenetic technique for physical mapping, chromosome marker screening, and comparative genomics. As a large genomic fragment with repetitive sequences is inserted in each BAC clone, random BAC FISH without adding competitive DNA can unveil complex chromosome organization of the repetitive elements in plants. Here we performed the comparative analysis of the random BAC FISH in monocot plants including species having small chromosomes (rice and asparagus) and those having large chromosomes (hexaploid wheat, onion, and spider lily) in order to understand a whole view of the repetitive element organization in Poales and Asparagales monocots. More unique and less dense dispersed signals of BAC FISH were observed in species with smaller chromosomes in both the Poales and Asparagales species. In the case of large-chromosome species, 75-85% of the BAC clones were detected as dispersed repetitive FISH signals along entire chromosomes. The BAC FISH of Lycoris did not even show localized repetitive patterns (e.g., centromeric localization) of signals.

DNA methylation and histone modification in onion chromosomes.

Onion, Allium cepa, is a model plant for experimental observation of somatic cell division, whose mitotic chromosome is extremely large, and contains the characteristic terminal heterochromatin. Epigenetic status of the onion chromosome is a matter of deep interest from a molecular cytogenetic point of view, because epigenetic marks regulate chromatin structure and gene expression. Here we examined chromosomal distribution of DNA methylation and histone modification in A. cepa in order to reveal the chromatin structure in detail. Immunodetection of 5-methylcytosine (5mC) and in situ nick-translation analysis showed that onion genomic DNA was highly methylated, and the methylated CG dinucleotides were distributed in entire chromosomes. In addition, distributions of histone methylation codes, which occur in close association with DNA methylation, were similar to those of other large genome species. From these results, a highly heterochromatic and less euchromatic state of large onion chromosomes were demonstrated at an epigenetic level.

Predicting nodal status using dynamic contrast-enhanced magnetic resonance imaging in patients with locally advanced breast cancer undergoing neoadjuvant chemotherapy with and without sequential trastuzumab.

HYPOTHESIS: Dynamic contrast-enhanced (DCE) magnetic resonance imaging (MRI) is a reliable and accurate method for monitoring primary tumor response in the breast and can be used as a surrogate to predict final axillary nodal status. DESIGN: Retrospective study (October 1, 2004, through February 28, 2006) of 46 patients with clinically staged locally advanced breast cancer. SETTING: Comprehensive cancer center. PATIENTS: Forty-six patients with locally advanced breast cancer. INTERVENTIONS: Neoadjuvant chemotherapy (NAC), DCE-MRI, mastectomy and lumpectomy, and axillary lymph node dissection. MAIN OUTCOME MEASURES: The DCE-MRI results and pathologic response of the breast and axillary lymph nodes. RESULTS: Forty-six patients underwent NAC with doxorubicin hydrochloride and cyclophosphamide, followed by paclitaxel and carboplatin, with or without trastuzumab based on human epidermal growth factor receptor 2 (HER2/neu) status. Twenty-one patients (46%) had a complete pathologic response. For the HER2/neu-positive patients, the complete pathologic response rate was 70% (14/20). The accuracy, sensitivity, and specificity of the primary tumor response in predicting the axillary nodal status were 78%, 88%, and 72%, respectively. The accuracy, sensitivity, and specificity of the DCE-MRI-measured response in the primary tumor in predicting axillary nodal status were 74%, 62%, and 82%, respectively. For the HER2/neu-positive patients, the accuracy, sensitivity, and specificity improved to 80%, 75%, and 82%, respectively. CONCLUSIONS: The results of DCE-MRI of the primary tumor can be predictive of axillary nodal status, especially in patients receiving trastuzumab who are HER2/neu positive. The HER2/neu-positive patients with a complete clinical response on DCE-MRI are highly unlikely to benefit from an axillary lymph node dissection. For HER2/neu-negative patients, sentinel lymph node sampling is warranted.